News — Washington D.C. – Among adult Americans saying they are eating either a low-carbohydrate or low-fat diet pattern, remarkably few achieve what nutrition experts would consider low.
Results from a recently published study indicate that health professionals will be misinformed if they simply ask patients if they are eating a diet low in carbohydrate or fat.
The new reported on over 30,000 adult Americans in a nationally representative cross-sectional analysis. Results show that only 1.4% of US adults over 20 years of age say that they eat a low-carbohydrate diet.
Remarkably, based on two, 24-hour self-reported food intakes, only 4.1% of those few people saying they eat low-carb diets consumed <26% total energy as carbohydrates. While these adults may be aiming to limit their intake of carbohydrates, they are not achieving a low-carbohydrate diet. Instead, almost 40% ate diets <35% of energy as carbohydrates, which means the majority of adults who report eating low-carbohydrate diets actual eat a diet that could be characterized as “carbohydrate restricted” but not “low carbohydrate.”
Adherence to low-fat diets was better than for low-carbohydrate diets, even among those who did not report eating low-fat. For example, 23% of those saying they eat a low-fat diet consumed <30% energy from fat.
The authors emphasize the need for clinicians and public health professionals to be cautious when interpreting individuals’ self-reported diet patterns. The article also encourages them to collect more detailed dietary data when possible.
The , “Are People Consuming the Diets They Say They Are? Self-Reported vs. Estimated Adherence to Low-Carbohydrate and Low-Fat Diets: National Health and Nutrition Examination Survey, 2007-2018,” appears in the peer-reviewed Journal of the Academy of Nutrition and Dietetics.
The research was conducted at William & Mary and supported by IAFNS . The size and representative nature of the survey allows the conclusions to be applied nationally and the findings bear on both researchers and clinicians.
According to the authors, “Clinicians should be cautious about the validity of their patients’ reports of adherence to specialized diets and may request more detailed follow-up information about consumption of key food groups to reduce measurement bias.”
The researchers also had advice for future evaluations of diet quality across large groups. Such broad reviews are relied on by researchers, managers, policymakers and administrators.
“When assessing the prevalence of diet patterns in large populations, researchers should pay careful attention to distinguish between self-reported vs. estimated adherence to diet patterns,” according to the paper.
Senior author Zach Conrad, an Assistant Professor at William & Mary, says, “To fully understand what people are eating, you need to ask them. But this research shows that the way you ask them matters. That can make a big difference in how researchers monitor diet trends, and in the care that people receive from health professionals.”
The study is available .
The Institute for the Advancement of Food and Nutrition Sciences (IAFNS) is committed to leading positive change across the food and beverage ecosystem. This paper was supported by IAFNS . IAFNS is a 501(c)(3) science-focused nonprofit uniquely positioned to mobilize government, industry and academia to drive, fund and lead actionable research.
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